Concentration of ores.



UNITED STATES'PATE FFICE.

ARTHUR HOWARD HIGGINS, or

MENTS, TO MINERALS SEPARATION NORTH AMERICAN CORPORATION.

CONCENTRATION OF ORES;

mi Drawing. Application filed September 23, 1914, Serial No. 863,097.

To all whom z'tzmay concern Be it' known that I, ARTHUR HOWARD H eoms, a subject of the Kingv of England, residing at 62 London Wally-London, England,

have invented-certain new andu'seful 11m provement's-in the Concentration of Ores, of which the following is a specification.

Thisinventionis for improvements in or relating to the concentration. of ores and especially to preferential or selective flotation, that is to say tothe separation of differentmetallic sulfids from one another aswell as from gangue when flotation processes tention 'will'be "particularly directed to apparatus ofthe sub-aerator type described in my United States Patent No. 1,155,816, issued October 5, 1915, that is to, say, to a flotation apparatus in which the particles in the pulp in a comparatively quiet zone in the upper portion of the flotation vessel are subjected to the action of a continuous stream of innumerable minute gaseous bubbles rising to a froth outlet at the top.

An important factor in froth flotation processes is the tendency of a particle to be wetted by water, and conversely the tendency of a particle to become dry or to becom eiattacheol to a gaseous bubble. The 'gangue particles have the greatest tendency to be wetted by water, and have the least tendency to be attached to' gaseous bubbles.

Further comparing galena' and blends, for example, particles of galena appear to have the least tendency to, be Wetted with Water or the greatest tendency to become attached to gaseous bubbles, While blende particles appear to have a somewhat smaller tendency to be attached to gaseous bubbles. Pyrites appear to have a still greater tendency than galena to be attached to gaseous bubbles.

In a flotation process, particularly if carried out in an apparatus of the type above referred to, it is found that if a finely crushed 'orc carryinggalena and blends be subjected to classification so as to obtain products containing particles haying sub- Specification of Letters Patent.

process so as to of this invention, it is desirable first Patented Aug. 14, 1917.

Renewed June 2, i916. Serial No.

stantially the same rate of fall in water,-and 1f such-products are subjected to preferential flotation, the determining factor is the tendency of the attachment to air bubbles. For this reason the galena has the greatest tendency to float. v.

This invention, therefore, is embodied in inwhich the finely crushed ore is classified so as to yield products containing particles having substantially the same rate of fall in Water, whereupon these products are sepa rately treated by a preferential flotation relatively high in a certain sulfid on the one hand and residues relatively high in another sulfid on the other hand.

In carrying this invention into effect it is found that the conditions most suitable for preferential or selective flotation are as folows:-

The frothing agent employed should be partly soluble in water, amygdalina, and the should be very small about 1 or 2 ounces per ton of ore treated; e. for 4 tons of.

water). Additions of frothing agent may be made during the treatment if it is desired to increase the rate at which the froth is produced, care being taken to avoid excess. In a number of previous patents relating to this subject reference has been made to the use of solutes, such as acids, alkalis and soluble salts to assist the selection of the air bubbles. A process embodying this invention may involve. the use of these agents, and a simple preliminary test of any particular ore would determine the chemical constitu? tion of the solution to be employed. In most of the experiments which led to the present invention the pulp was alkaline containing about 0.1 to 0.3 per cent. of'sodium carbonate in solution. Successful results have also been obtained with other salts, such as sodium bicarbonate and sodium sulfate. Y

The invention is particularly applicable member of the series of classified products.

obtain flotation products Absolute LONDON, ENGLAND, -ASSIGNOR, BY ME SNE ASSIGN- I a process for the selective separation of the. different constituents of an ore by flotation,

such as eucalyptus roportion employed to finely crushed .materials, and the more I It was then agitated for 5 minutes in which \Vith classified products the air attachment factor is predominant, so that galena will float in preference to blende, for example, provided there is no chemical agent present which interferes with the relative wet lyptus per ton ofore and the mixture was agitated for three minutes, during which the first part of the concentrate was removed.

the second part of the concentrate was removed and then agitated for 4: minutes during which the third part of the concentrate was removed. Therewas then added 3 OZS. more of eucalyptus per ton of ore and the mixture was agitated for 6 minutes, during which the fourth part of the concentrate was v lied products separately to froth flotation treatment so as to preferentially float one of removed. The results offthese four concentrations were as follows Proportion A553 yo! gg gggg concentrate. Recovery 7.9% Zn. 2 07 Zn 5. 68.8 Pb. v I 0% g lama, Pb. 26.8% Zn. 184W Zn 113% ig 3% liarygrb 55 17 Zn '7 U I a l 313% l W Pb 41.3 211. 19 z 8. 2.2; Pb. i as Ins l P- may be seriously interfered withif'the proportion of solute or of frothing agent be excessive or insuflicient; and from the above directions it will be obvious that a few simple preliminary tests will determine the best conditions.

What I claim as my invention and desire to secure by Letters Patent is 1. A process of concentrating-ores con taining mixed metalliferous minerals which consists in classifying such an .ore so as to obtain a plurality of products one of which products is composed of particles having substantially the same rate of fall in water, and

thereafter subjecting such classified product to froth flotation treatmentso. as to preferentially float one of the metalliferous minerals.

.2. A process of concentrating fores contaming mixed metalhferous minerals which consists in classifying such an ore so as-to obtain a plurality of products one of which is composed of particles having substantially the same rate'of fall in water, and thereafter subjecting such classified product to froth flotation treatment so as to obtain a flotation product relatively high in a certain metalliferous mineral on the one hand and a residue relatively high in another metalliferous mineral on the other hand, and submitting the residue to further froth flotation treatment for the recovery of the metalliferous mineral contained therein- 3. A process of concentrating ores containing mixed metalliferous minerals which consists in classifying such an ore in finely crushed condition so as to obtain a plurality of products. each composed of particles having substantially the same rate of fall in water, and thereafter subjecting such classithe metalliferous minerals.

4. A process of concentrating ores c0ntaining mixed metalliferous minerals which consists in classifying such an ore in finely crushed condition so as to obtain a plurality of products each composed of particles having substantially the same rate of fall in Water, and thereafter subjecting the prod;-

ucts separately to froth flotation treatment so as to. obtain flotation products relatively high in a certain metalliferous mineral on the one hand and residues relatively high in an-- other metalliferous mineral on the other hand, and submitting-the residues tofurther froth flotation treatment for the recov ery of the metalliferous mineral containedtherein.

5. A. process of concentrating ores contain ing mixed metalliferous minerals which consists in classifying such an ore so as to obtain a plurality of roducts one of which products is composed 0 particles having substantially the same rate of fall in water, and thereafter subjecting such classified roduct to froth flotation treatment with 511 aeration so as to preferentially float one of the metalliferous minerals. Y

6. A process of concentrating ores containing mixed metallife'rous minerals which consists in classifying such an oreso as to obtain a plurality of products one of which is composed of particleshaving substantially the same rate of fall in water, and thereafter masses subjecting such classifiled product to froth flotation'treatment with sub'aeration so as to obtain a flotation product relatively high in a. certain metalliferous mineral on the .one

hand and a a residue relatively high in.

another metalliferous mineral on the other hand, and submitting the residue to further froth flotation treatment for the recovery of the metalliferous mineral contained therein.

7. A process of concentrating ores containing mixed metalliferous minerals which consists in classifying such an ore in finely crushed condition so as to obtain a plurality of products each composed of particles having substantially the sameyrate of fall in water, and thereafter subjecting such classified products separately to froth flotation treatment with subaeration so as to preferentially float one of the metalliferousmin- 8. A process of concentrating ores containing mixed metalhferous minerals which consists in classifying such an ore 1n finely crushed condition so as to obtain a plurality of products each composed of particles having substantially the same rate of .fall in water, andthereafter subjecting the products separately to froth flotation treatment with subaeration so asto obtain flotation products relatively high in a certain metalliferous mineral on the one hand and residues relatively highin another metalliferous mineral .on the other hand, and submitting theresidues to further froth flotation treatment for the recovery of the metalliferous mineral contained therein.

9. A process of concentrating zinc-lead stantially the same rate of fall in Water, and

thereafter subjecting such classified product to froth flotation treatment so as to obtain a flotation product relatively high in lead on the one hand and a residue relatively high in zinc on the other hand, and submitting the residue to further froth flotation treatment for the recovery of the zinc contained therein.

11. A process of concentrating zinc-lead ores which consists in classifying such an ore in finely crushed condition so as to obtain a plurality of productseach composed of particles having 'substantiallv the same rate-of fall in Water, and thereafter subjecting such classified products separately i to froth flotation treatment so as to obtain aflotation product relatively high in lead on the one hand and a residue relatively high in zinc on the other hand.

. 12. A process of concentrating zinc-lead ores which consists in classifying such an ore in finely crushed condition so as to ob: tain a plurality of-products each. composed of particles having substantially the same-j rate of fall in Water, and thereafter sub-,.

jecting the products separately to froth flotation treatment so as to obtain flotation products relatively high in lead on the one hand and residues relatively high in zinc on the, other hand, and submitting the residues to further froth flotation treatment for .the recovery of zinc contained therein.

13. A process of concentrating zinc-lead ores which consists in classifying such an ore so as to obtain a plurality of products one of which products is composed of particles having substantially the same rate of fall in Water and thereafter subjecting such classified product to froth flotation treat ment with subaeration so as to obtain a flotation product relatively high in lead on the one hand and a residue relatively high in zinc on the other hand.

p 14:. A process of concentrating zinc-lead ores which consists in classifying such an ore so as to obtain a plurality of products one of which is composed of particles having substantially the same rate of fall in water, and thereafter subjecting such classified product to froth flotation treatment with subaeration so as to obtain a flotation product relatively high in lead on the one hand and a residue relatively high in zinc on the other hand, and submitting the residue to further froth flotation treatment for the recovery of the zinc contained therein.

15. A process of concentrating zinc-lead ores which consists in classifying such an ore in finely crushed condition'so as to obtain a plurality of products each composed .of particles having substantially the same rate of fall in water, and thereafter subjecting such classified products separatel to froth flotation treatment with subaer 7; tion so as to obtain a flotation product rela tively high in lead on the one hand and a residue relatively high in zinc on the other hand.

16. A process of concentrating zinc-lead 'i is ores which consists in classifying such an' ore in finely cru'shed condition so as to obtain a plurality of products each composed of particles having substantially the same rate of fall in Water, and thereafter sub jecting the products separately to froth flo-,

tation treatment with subaeration so as to obtain flotation. products relatively high in lead on the one hand and residues relatively high in zinc on the other hand, and submitting the residues to further froth flotation treatment for the recovery of zinc contained therein.

17. A process of concentrating zinc-lead ores which consists in classifying such an ore so as to obtain a plurality of products one of which products is composed of particles having substantially the same rate of fall in Water, and thereafter subjecting such classified product to froth flotation treat-- ment with subaeration in the presence of a. minute quantity of eucalyptus oil so as to obtain a flotation product relatively high in 15 lead on the one hand and a residue relatively high in zinc on the other hand.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ARTHUR HOWVARD HIGGINS. lVitnesses VILLIAM JAMES WALTON,

GEORGE BUTTON. 

